In designing a product, e.g., in designing a circuit, a designer draws a circuit diagram (CAD diagram) using a CAD (Computer Aided Design) system, then selects parts to be used in the drawn circuit.
Selection of parts to be used in a circuit by a designer is carried out in consideration of the specification (spec) of the circuit, such as the performance demanded of the circuit and the size thereof. However, information on parts is often managed individually group by group or section by section, so that there may be a case where a designer has a difficulty in selecting optimal parts. In this respect, there is a system which collectively manages information on parts to facilitate selection of parts by a designer (see, for example, Unexamined Japanese Patent Application KOKAI Publication No. 2002-99591).
In a case where a designer draws a circuit diagram, circuit diagrams already designed are often used. But, information on circuits including circuit diagrams is often managed individually designer by designer or group by group. Therefore, it may not be possible to use circuit diagrams drawn by designers of different groups, for example, bringing about a problem of poor management efficiency.
In designing a circuit, layout of parts should be considered in order to determine optimal positions of parts to be used in the circuit. Consideration of layout of parts requires that detailed circuit diagrams indicating to the pins of which parts the pins of parts constituting a circuit are connected should be drawn for various layouts of the parts, and it should be confirmed that each circuit diagram drawn contains no logical misses. Determining the optimal positions of parts to be used in the circuit is therefore a time-consuming work.
Further, in designing a circuit, restrictions on circuit implementation, e.g., shape limitations, such as a height limitation, and performance limitations, such as a thermal limitation, should be considered in addition to design rules and wiring rules.